Corrosive and burning, but also interchangable for the word awesome.
"Man, when that shopping cart hit that wino, that was caustic"
"I went to this caustic party downtown, but then someone got stabbed"
"Sally is pretty caustic, when she's not hanging out with that pilgrim Luke"
A really white guy who looks like he'd wear a four cornered hat and or make bread. Racist towards white people, can be used interchangably with any insult in a sentence if they are white.
"Hey, look at me, fuck you Pilgrim"
"Look at the khakis Luke is wearing, he is suching a fucking pilgrim"